Direct supply pressure difference isolation station wisdom system and working method thereof

Abstract

The present application relates to the field of pressure isolation station, specifically to a direct supply temperature difference free pressure isolation station intelligent system and a working method thereof, the present application uses the direct supply temperature difference free pressure isolation station intelligent system to replace the original heat exchanger pressure isolation station, uses a booster pump, a pressure reducing valve and a series of safety measures, without twice heat exchange, directly transports the primary network hot water to the heat station for heat exchange, solves the problem of temperature difference on both sides after the first and second pipe networks pass through the heat exchanger of the pressure isolation station, solves the problem of too high return water temperature caused by pipe network water quality, heat exchange efficiency and the like, and improves the heating effect.

Description

Technical Field

[0001] This invention relates to the field of pressure reducing stations, specifically to a direct-supply, temperature-difference-free pressure reducing station intelligent system and its working method. Background Technology

[0002] The heat exchanger pressure isolation station system of the heating system needs to perform two heat exchanges to provide heat to users. That is, the heat exchange is first carried out through the pressure isolation station, and the exchanged hot water is transported to the heating station. The heating station then performs a second heat exchange. This results in the high temperature of the primary return water of the pressure isolation station and the low temperature of the secondary supply water of the heating station, resulting in insufficient heat supply.

[0003] In other words, because there is a temperature difference between the primary and secondary pipe networks after heat exchange through the heat exchanger at the pressure relief station, when the secondary pipe network uses a large temperature difference heating system, due to factors such as water quality and heat exchange efficiency, it cannot be guaranteed that the return water from the primary pipe network will stably meet the design requirements. When the secondary pipe network uses conventional supply and return water temperature difference heating, the required heating effect cannot be achieved. Summary of the Invention

[0004] The purpose of this invention is to provide a direct-supply, temperature-difference-free pressure-reducing station intelligent system and its working method to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a direct-supply, temperature-difference-free pressure-reducing station intelligent system, comprising a primary network water supply pipe and a primary network return pipe. The output end of the primary network water supply pipe is connected to the secondary external network in sequence via a manual butterfly valve VM1, an electric butterfly valve VE1, an electric pressure regulating valve VR1, an electric pressure regulating valve VR3, and a manual butterfly valve VM7. The input end of the primary network water supply pipe is connected to the primary external network. The output end of the primary network return pipe is connected to circulating pumps Pu2 and Pu4 in sequence via a manual butterfly valve VM8. The output ends of circulating pumps Pu2 and Pu4 are connected to the primary external network in sequence via a check valve, an electric butterfly valve VE2, and a manual butterfly valve VM2. The input end of the primary network return pipe is connected to the secondary external network.

[0006] Preferably, a pressure sensor PT1 and a pressure gauge PD1 are installed at the front end of the electric butterfly valve VE1, and a temperature sensor TT1, a pressure sensor PT3, and a pressure gauge PD3 are installed at the rear end of the electric butterfly valve VE1.

[0007] Preferably, a pressure sensor PT2 and a pressure gauge PD2 are installed at the rear end of the electric butterfly valve VE2, and a temperature sensor TT2, a pressure sensor PT4, and a pressure gauge PD4 are installed at the front end of the electric butterfly valve VE2.

[0008] Preferably, the electric pressure regulating valve VR1 is connected in parallel with the manual butterfly valve VM3, and a pressure sensor PT5 and a pressure gauge PD5 are installed between the electric pressure regulating valve VR1 and the electric pressure regulating valve VR3, and the electric pressure regulating valve VR3 is connected in parallel with the manual butterfly valve VM5.

[0009] Preferably, a pressure sensor PT7, a pressure gauge PD7, and a thermometer TD1 are installed at the front end of the manual butterfly valve VM7, and a pressure sensor PT8, a pressure gauge PD8, and a thermometer TD2 are installed at the rear end of the manual butterfly valve VM8.

[0010] Preferably, the circulating pump Pu2 and the circulating pump Pu4 are connected in parallel, and manual butterfly valves are installed at both ends of the circulating pump Pu2 and the circulating pump Pu4 respectively.

[0011] Preferably, the signal output terminals of the pressure sensor PT1, pressure gauge PD1, electric butterfly valve VE1, temperature sensor TT1, pressure sensor PT3, electric pressure regulating valve VR1, pressure sensor PT5, electric pressure regulating valve VR3, pressure sensor PT7, pressure sensor PT2, electric butterfly valve VE2, temperature sensor TT2, pressure sensor PT4, circulating pump Pu2, circulating pump Pu4, and pressure sensor PT8 are connected to a controller. The controller is connected to the analog expansion module of the PLC controller in the control cabinet, and the analog expansion module of the PLC controller is connected to the touch screen via a network cable.

[0012] A preferred method for operating a direct-supply, temperature-difference-free pressure-reducing station intelligent system includes the following steps:

[0013] Step S1, System Start-up Preparation: Check that the system instruments and valves are working normally. If any abnormalities are found, replace, repair or calibrate them in a timely manner.

[0014] Step S2, Equipment Selection: When the electric pressure regulating valves VR1 and VR3 are functioning properly, both electric pressure regulating valves will operate. If one of them fails, the other will take on all pressure reduction tasks and bypass the failed pressure regulating valve. Circulating pumps Pu2 and Pu4 will be used in pairs, with one pump selected for operation based on the operating time and pump status.

[0015] Step S3, Parameter Setting: Electric pressure regulating valves VR1 and VR3 are set to manual or automatic start mode according to the number of operating units. When using automatic adjustment mode, set the target pressure reduction value at startup, the target pressure reduction value during normal operation, and the dead zone. When using manual start mode, set the opening degree at startup and the opening degree during normal operation. The circulating pump is set to one of the following: constant outlet pressure difference automatic adjustment, proportional automatic adjustment of outlet and inlet pressure difference, or manual frequency setting. When using constant outlet pressure difference automatic adjustment, set the target outlet pressure difference value at startup, the target outlet pressure difference value during normal operation, and the dead zone. When using proportional automatic adjustment of outlet and inlet pressure difference, set the target outlet pressure difference value at startup, the target outlet pressure difference value during normal operation, and the dead zone. When using manual frequency setting, set the frequency at startup and the frequency during normal operation.

[0016] Step S4, Alarm Value Setting: Set the upper limit of outlet water supply pressure, the lower limit of outlet return water pressure, the upper limit of water supply temperature, power outage alarm, and abnormal pump stop alarm according to operational requirements;

[0017] Step S5: After completing steps S1-S4, start the system according to the set parameters.

[0018] Preferably, the specific startup process for the manual startup mode in step S3 is as follows:

[0019] Step a: After confirming that the instruments and valves are working properly, inject water into the primary water supply pipe to bring the system pressure to 0.25MPa. When injecting water, first manually open the electric butterfly valve VE1, then open the manual butterfly valves VM3, VM5, VM7, and VM8. Manually open the manual butterfly valve VM1 to about 5% of its opening, which needs to be adjusted in real time according to the rate of pressure change. Start injecting water into the system, closely monitor the system pressure, the water pump inlet pressure, pressure gauge PD8, and pressure sensor PT8. Ensure that the air vent valve is unobstructed during water injection. When the pressure reaches 0.25MPa, close the manual butterfly valve VM1. After closing the manual butterfly valve VM1, observe whether the system pressure drops. If it drops, vent and inject water again until the pressure stabilizes.

[0020] Step b: After the pressure stabilizes, close the electric butterfly valve VE1, manual butterfly valves VM1, VM2, VM3, and VM5, while keeping manual butterfly valves VM7 and VM8 open. Start the water pump and slowly increase the speed. Simultaneously, open the electric pressure regulating valves VR1 and VR3. Reduce the pressure of electric pressure regulating valve VR1 to 0.5MPa and VR3 to 0.3MPa. Manually or automatically adjust the water pump frequency to reach the set parameters and run for at least 10 minutes. During this period, observe the water pump supply and return pressures and the pressure after the pressure regulating valves, and vent the air in time. If the water pump inlet pressure is too low, manually open the manual butterfly valve VM1, ensuring the opening degree of manual butterfly valve VM1 is no more than 5%, to replenish water.

[0021] Step c: After the operating parameters of electric pressure regulating valves VR1 and VR3 have reached a safe and reasonable state, open electric butterfly valves VE1 and VE2, and manually and slowly open manual butterfly valves VM1 and VM2. Observe the water pump supply and return pressures and the pressure after the electric pressure regulating valves. Manually or automatically adjust the water pump frequency to ensure a reasonable flow rate. After the water pump supply and return pressures and the electric pressure regulating valves have stabilized for 5 minutes, the program will automatically increase the pressure reduction value of electric pressure regulating valve VR1 to 0.65MPa and the pressure reduction value of electric pressure regulating valve VR3 to 0.45MPa. The water pump will be set to a reasonable value so that its flow rate reaches the required flow rate.

[0022] Preferably, the automatic startup mode startup process in step S3 is as follows:

[0023] Step 1: Put manual butterfly valves VM1, VM2, VM7, and VM8 into the open state; and electric butterfly valves VE1, VE2, VM3, and VM5 into the closed state.

[0024] Step II: After confirming that the instruments and valves are working properly, inject water into the primary water supply pipe to bring the system pressure to 0.25 MPa. If the system has already been injected with water and the pressure has reached 0.25 MPa, skip this step. When injecting water, first automatically open the electric butterfly valve VE1, with the opening degree of electric butterfly valve VE1 being about 5%. Then open the electric pressure regulating valves VR1 and VR3. When the pressure sensor PT8 reaches 0.25 MPa, close the electric butterfly valve VE1. After closing the electric butterfly valve VE1, wait for 1 minute and observe whether the system pressure has decreased. If it has decreased, vent the air and inject water again until the pressure stabilizes.

[0025] Step III: After the pressure stabilizes, close the electric butterfly valves VE1 and VE2, start the water pump, and slowly increase the speed. At the same time, open the electric pressure regulating valves VR1 and VR3. Reduce the pressure of electric pressure regulating valve VR1 to 0.5MPa and electric pressure regulating valve VR3 to 0.3MPa. Automatically adjust the water pump frequency to bring the water pump to the set parameters and run for at least 10 minutes. During this period, if the water pump inlet pressure is too low, automatically open the electric butterfly valve VE1 to replenish water until the pressure sensor PT8 reaches 0.25MPa.

[0026] Step IV: After the operating parameters of the water pump, electric pressure regulating valve VR1, and electric pressure regulating valve VR3 have all reached a stable state, slowly open the electric butterfly valves VE1 and VE2. After the water pump supply and return pressures and the pressure regulating valves have stabilized for 5 minutes, slowly increase the pressure reduction value of electric pressure regulating valve VR1 to 0.65MPa and the pressure reduction value of electric pressure regulating valve VR3 to 0.45MPa. Also, set the water pump to a reasonable value so that the system flow rate reaches the required flow rate.

[0027] Step V: Once the operating parameters are normal, it is considered to be in normal operating condition.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention replaces the original heat exchanger pressure isolation station with a direct-supply pressure isolation station intelligent system. By using a booster pump, pressure reducing valve and a series of safety measures, the primary network hot water is directly delivered to the heating station for heat exchange without the need for two heat exchange processes. This solves the problem of temperature difference between the two sides of the primary and secondary pipe networks after heat exchange through the pressure isolation station heat exchanger, and also solves the problem of excessively high return water temperature caused by factors such as pipe network water quality and heat exchange efficiency, thereby improving the heating effect. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the system structure of the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] In the description of this invention, it should be noted that the terms "vertical," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0032] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] Please see Figure 1 This invention provides a technical solution: a direct-supply, temperature-difference-free pressure-reducing station intelligent system, comprising a primary network water supply pipe and a primary network return pipe. The output end of the primary network water supply pipe is connected to the secondary external network in sequence through a manual butterfly valve VM1, an electric butterfly valve VE1, an electric pressure regulating valve VR1, an electric pressure regulating valve VR3, and a manual butterfly valve VM7. The input end of the primary network water supply pipe is connected to the primary external network. The output end of the primary network return pipe is connected to circulating pumps Pu2 and Pu4 in sequence through a manual butterfly valve VM8. The output ends of circulating pumps Pu2 and Pu4 are connected to the primary external network in sequence through a check valve, an electric butterfly valve VE2, and a manual butterfly valve VM2. The input end of the primary network return pipe is connected to the secondary external network.

[0034] Furthermore, a pressure sensor PT1 and a pressure gauge PD1 are installed at the front end of the electric butterfly valve VE1, and a temperature sensor TT1, a pressure sensor PT3, and a pressure gauge PD3 are installed at the rear end of the electric butterfly valve VE1.

[0035] Furthermore, a pressure sensor PT2 and a pressure gauge PD2 are installed at the rear end of the electric butterfly valve VE2, and a temperature sensor TT2, a pressure sensor PT4, and a pressure gauge PD4 are installed at the front end of the electric butterfly valve VE2.

[0036] Furthermore, an electric pressure regulating valve VR1 is connected in parallel with a manual butterfly valve VM3, and a pressure sensor PT5 and a pressure gauge PD5 are installed between the electric pressure regulating valve VR1 and the electric pressure regulating valve VR3. The electric pressure regulating valve VR3 is also connected in parallel with the manual butterfly valve VM5.

[0037] Furthermore, pressure sensor PT7, pressure gauge PD7, and thermometer TD1 are installed at the front end of manual butterfly valve VM7, and pressure sensor PT8, pressure gauge PD8, and thermometer TD2 are installed at the rear end of manual butterfly valve VM8.

[0038] Furthermore, circulating pumps Pu2 and Pu4 are connected in parallel, and manual butterfly valves are installed at both ends of circulating pumps Pu2 and Pu4 respectively.

[0039] Furthermore, the signal output terminals of pressure sensor PT1, pressure gauge PD1, electric butterfly valve VE1, temperature sensor TT1, pressure sensor PT3, electric pressure regulating valve VR1, pressure sensor PT5, electric pressure regulating valve VR3, pressure sensor PT7, pressure sensor PT2, electric butterfly valve VE2, temperature sensor TT2, pressure sensor PT4, circulating pump Pu2, circulating pump Pu4, and pressure sensor PT8 are connected to a controller. The controller is connected to the analog expansion module of the PLC controller in the control cabinet, and the analog expansion module of the PLC controller is connected to the touch screen via a network cable.

[0040] Furthermore, a working method for a direct-supply, temperature-difference-free pressure-reducing station intelligent system includes the following steps:

[0041] Step S1, System Start-up Preparation: Check that the system instruments and valves are working normally. If any abnormalities are found, replace, repair or calibrate them in a timely manner.

[0042] Step S2, Equipment Selection: When the electric pressure regulating valves VR1 and VR3 are functioning properly, both electric pressure regulating valves will operate. If one of them fails, the other will take on all pressure reduction tasks and bypass the failed pressure regulating valve. Circulating pumps Pu2 and Pu4 will be used in pairs, with one pump selected for operation based on the operating time and pump status.

[0043] Step S3, Parameter Setting: Electric pressure regulating valves VR1 and VR3 are set to manual or automatic start mode according to the number of operating units. When using automatic adjustment mode, set the target pressure reduction value at startup, the target pressure reduction value during normal operation, and the dead zone. When using manual start mode, set the opening degree at startup and the opening degree during normal operation. The circulating pump is set to one of the following: constant outlet pressure difference automatic adjustment, proportional automatic adjustment of outlet and inlet pressure difference, or manual frequency setting. When using constant outlet pressure difference automatic adjustment, set the target outlet pressure difference value at startup, the target outlet pressure difference value during normal operation, and the dead zone. When using proportional automatic adjustment of outlet and inlet pressure difference, set the target outlet pressure difference value at startup, the target outlet pressure difference value during normal operation, and the dead zone. When using manual frequency setting, set the frequency at startup and the frequency during normal operation.

[0044] The three modes of the circulating pump—constant automatic adjustment of outlet pressure difference, automatic adjustment of outlet pressure difference proportional to inlet pressure difference, and manual frequency setting—are as follows:

[0045] Automatic adjustment of constant outlet differential pressure: given dP_pump, default 0.1MPa, and between dP_pump_max (default 0.2MPa) and dP_pump_min (default 0.02MPa), feedback (PT7-PT8);

[0046] Automatic proportional regulation of outlet pressure difference and inlet pressure difference: The outlet pressure difference is ratio times the inlet pressure difference, and dP_pump = ratio * (PT1 - PT2) is given; when ratio * (PT1 - PT2) > dP_pump_max, dP_pump_max is taken, and when ratio * (PT1 - PT2) < dP_pump_min, dP_pump_min is taken; feedback (PT7 - PT8), where the outlet pressure difference of the pressure separation station is greater than the given pressure difference PT7 - PT8 > dP_pump + P_pump_band or PT7 - PT8 < dP_pump - P_pump_band, and P_pump_band defaults to 0.01 MPa and can be modified; if PID control is started, the outlet pressure difference PT7 - PT8 is controlled according to the given dP_pump; if it is not within the safe range P3 > P3_max - P_pump_band and the pump outlet pressure difference is less than the given pressure difference P3 - P4 < dP_pump + P_pump_band, PID regulation with P3 as the target is started to control P3 within the safe range. When reducing the pump frequency, if an overload abnormal situation occurs, the pump should be stopped and the valve should be closed interlockingly;

[0047] Manually given frequency: After determining the given value Pump_setpoin, judge whether the pump outlet pressure is within the safe range. If so, the frequency is given as follows in the table:

[0048] Inlet pressure difference (P1-P2) Water pump frequency P1-P2<0.10MPa 35Hz / setting, adjustable 0.17MPa > P1 - P2 > 0.10MPa 40Hz / setting, can be modified 0.25MPa > P1 - P2 > 0.17MPa 45Hz / setting, adjustable P1-P2>0.25MPa 50Hz / setting, can be modified

[0049] Step S4, Alarm value setting: Set the upper limit of the outlet water supply pressure, the lower limit of the outlet return water pressure, the upper limit of the water supply temperature, power failure alarm and abnormal pump stop alarm according to the operation requirements;

[0050] Step S5, After completing steps S1 - step S4, start the system according to the set parameters.

[0051] Furthermore, the specific start-up process of the manual start-up mode in step S3 is as follows:

[0052] Step a: After confirming that the instruments and valves are working properly, inject water into the primary water supply pipe to bring the system pressure to 0.25MPa. When injecting water, first manually open the electric butterfly valve VE1, then open the manual butterfly valves VM3, VM5, VM7, and VM8. Manually open the manual butterfly valve VM1 to about 5% of its opening, which needs to be adjusted in real time according to the rate of pressure change. Start injecting water into the system, closely monitor the system pressure, the water pump inlet pressure, pressure gauge PD8, and pressure sensor PT8. Ensure that the air vent valve is unobstructed during water injection. When the pressure reaches 0.25MPa, close the manual butterfly valve VM1. After closing the manual butterfly valve VM1, observe whether the system pressure drops. If it drops, vent and inject water again until the pressure stabilizes.

[0053] Step b: After the pressure stabilizes, close the electric butterfly valve VE1, manual butterfly valves VM1, VM2, VM3, and VM5, while keeping manual butterfly valves VM7 and VM8 open. Start the water pump and slowly increase the speed. Simultaneously, open the electric pressure regulating valves VR1 and VR3. Reduce the pressure of electric pressure regulating valve VR1 to 0.5MPa and VR3 to 0.3MPa. Manually or automatically adjust the water pump frequency to reach the set parameters and run for at least 10 minutes. During this period, observe the water pump supply and return pressures and the pressure after the pressure regulating valves, and vent the air in time. If the water pump inlet pressure is too low, manually open the manual butterfly valve VM1, ensuring the opening degree of manual butterfly valve VM1 is no more than 5%, to replenish water.

[0054] Step c: After the operating parameters of electric pressure regulating valves VR1 and VR3 have reached a safe and reasonable state, open electric butterfly valves VE1 and VE2, and manually and slowly open manual butterfly valves VM1 and VM2. Observe the water pump supply and return pressures and the pressure after the electric pressure regulating valves. Manually or automatically adjust the water pump frequency to ensure a reasonable flow rate. After the water pump supply and return pressures and the electric pressure regulating valves have stabilized for 5 minutes, the program will automatically increase the pressure reduction value of electric pressure regulating valve VR1 to 0.65MPa and the pressure reduction value of electric pressure regulating valve VR3 to 0.45MPa. The water pump will be set to a reasonable value so that its flow rate reaches the required flow rate.

[0055] Furthermore, the specific startup process for the automatic startup mode in step S3 is as follows:

[0056] Step 1: Put manual butterfly valves VM1, VM2, VM7, and VM8 into the open state; and electric butterfly valves VE1, VE2, VM3, and VM5 into the closed state.

[0057] Step II: After confirming that the instruments and valves are working properly, inject water into the primary water supply pipe to bring the system pressure to 0.25 MPa. If the system has already been injected with water and the pressure has reached 0.25 MPa, skip this step. When injecting water, first automatically open the electric butterfly valve VE1, with the opening degree of electric butterfly valve VE1 being about 5%. Then open the electric pressure regulating valves VR1 and VR3. When the pressure sensor PT8 reaches 0.25 MPa, close the electric butterfly valve VE1. After closing the electric butterfly valve VE1, wait for 1 minute and observe whether the system pressure has decreased. If it has decreased, vent the air and inject water again until the pressure stabilizes.

[0058] Step III: After the pressure stabilizes, close the electric butterfly valves VE1 and VE2, start the water pump, and slowly increase the speed. At the same time, open the electric pressure regulating valves VR1 and VR3. Reduce the pressure of electric pressure regulating valve VR1 to 0.5MPa and electric pressure regulating valve VR3 to 0.3MPa. Automatically adjust the water pump frequency to bring the water pump to the set parameters and run for at least 10 minutes. During this period, if the water pump inlet pressure is too low, automatically open the electric butterfly valve VE1 to replenish water until the pressure sensor PT8 reaches 0.25MPa.

[0059] Step IV: After the operating parameters of the water pump, electric pressure regulating valve VR1, and electric pressure regulating valve VR3 have all reached a stable state, slowly open the electric butterfly valves VE1 and VE2. After the water pump supply and return pressures and the pressure regulating valves have stabilized for 5 minutes, slowly increase the pressure reduction value of electric pressure regulating valve VR1 to 0.65MPa and the pressure reduction value of electric pressure regulating valve VR3 to 0.45MPa. Also, set the water pump to a reasonable value so that the system flow rate reaches the required flow rate.

[0060] Step V: Once the operating parameters are normal, it is considered to be in normal operating condition.

[0061] This invention, through the transformation of a direct-supply, temperature-difference-free pressure-reducing station intelligent system, eliminates the need for heat exchange at the primary network's heat exchange station. Instead, the hot water is directly delivered to the heating station after passing through the system, avoiding the insufficient heat exchange caused by the low heat exchange efficiency of the pressure-reducing station. The primary network's supply pressure to the pressure-reducing station is approximately 0.83 MPa, and the return pressure is approximately 0.8 MPa. Assuming a 35-meter elevation difference between the pressure-reducing station and the heating station, and considering the pressure-bearing capacity and operational safety of the heating station's equipment, this direct-supply, temperature-difference-free pressure-reducing station intelligent system can significantly improve the primary network's water supply... The pressure is reduced to about 0.43 MPa in the original pressure relief station, and the return water pressure is controlled to reach about 0.36 MPa in the pressure relief station. Then, the system pressurizes it to about 0.8 MPa and smoothly delivers it back to the primary network. During the coldest period, the high-temperature hot water of 95℃ in the primary network can be directly delivered to the heating station for heat exchange without the need for a pressure relief station. This can increase the secondary network water supply temperature from the original 43℃ to about 50-55℃, and reduce the primary network return water temperature from about 72℃ to about 47℃. This increases the temperature difference of the primary network water supply, improves the heat exchange efficiency, and fully meets the heating needs of users.

[0062] The renovation not only reduced the return water temperature of the primary network by more than 20°C, but also reduced the circulation flow of the primary network, improving the overall transmission efficiency of the heating network. It also eliminated the heat exchange process of the primary network pressure isolation station, increasing the indoor temperature of users in the heating area from the original 13°C to about 20°C, thus solving the problem of users' indoor heating temperature not meeting the standards.

[0063] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A direct-supply, temperature-difference-free pressure-reducing station intelligent system, comprising a primary network water supply pipe and a primary network return pipe, characterized in that: The output end of the primary water supply pipe is connected to the secondary external network via a manual butterfly valve VM1, an electric butterfly valve VE1, an electric pressure regulating valve VR1, an electric pressure regulating valve VR3, and a manual butterfly valve VM7. The input end of the primary water supply pipe is connected to the primary external network. The output end of the primary water return pipe is connected to circulating pumps Pu2 and Pu4 via a manual butterfly valve VM8. The output ends of circulating pumps Pu2 and Pu4 are connected to the primary external network via a check valve, an electric butterfly valve VE2, and a manual butterfly valve VM2. The input end of the primary water return pipe is connected to the secondary external network. A pressure sensor PT1 and a pressure gauge PD1 are installed at the front end of the electric butterfly valve VE1, and a temperature sensor TT1, a pressure sensor PT3, and a pressure gauge PD3 are installed at the rear end of the electric butterfly valve VE1. A pressure sensor PT2 and a pressure gauge PD2 are installed at the rear end of the electric butterfly valve VE2, and a temperature sensor TT2 and a pressure sensor PT4 are installed at the front end of the electric butterfly valve VE2. Pressure gauge PD4; the electric pressure regulating valve VR1 is connected in parallel with the manual butterfly valve VM3; a pressure sensor PT5 and a pressure gauge PD5 are installed between the electric pressure regulating valve VR1 and the electric pressure regulating valve VR3; the electric pressure regulating valve VR3 is connected in parallel with the manual butterfly valve VM5; a pressure sensor PT7, a pressure gauge PD7 and a thermometer TD1 are installed at the front end of the manual butterfly valve VM7; a pressure sensor PT8, a pressure gauge PD8 and a thermometer TD2 are installed at the rear end of the manual butterfly valve VM8; the circulating pump Pu2 and the circulating pump Pu4 are connected in parallel; and manual butterfly valves are installed at both ends of the circulating pump Pu2 and the circulating pump Pu4 respectively. The signal output terminals of the pressure sensor PT1, pressure gauge PD1, electric butterfly valve VE1, temperature sensor TT1, pressure sensor PT3, electric pressure regulating valve VR1, pressure sensor PT5, electric pressure regulating valve VR3, pressure sensor PT7, pressure sensor PT2, electric butterfly valve VE2, temperature sensor TT2, pressure sensor PT4, circulating pump Pu2, circulating pump Pu4, and pressure sensor PT8 are connected to a controller. The controller is connected to the analog expansion module of the PLC controller in the control cabinet, and the analog expansion module of the PLC controller is connected to the touch screen via a network cable.

2. The working method of the intelligent system for direct supply of temperature difference-free pressure isolation station according to claim 1, characterized in that, Includes the following steps: Step S1, System Start-up Preparation: Check that the system instruments and valves are working normally. If any abnormalities are found, replace, repair or calibrate them in a timely manner. Step S2, Equipment Selection: When the electric pressure regulating valves VR1 and VR3 are functioning properly, both electric pressure regulating valves will operate. If one of them fails, the other will take on all pressure reduction tasks and bypass the failed pressure regulating valve. Circulating pumps Pu2 and Pu4 will be used in pairs, with one pump selected for operation based on the operating time and pump status. Step S3, Parameter Setting: Electric pressure regulating valves VR1 and VR3 are set to manual or automatic start mode according to the number of operating units. When using automatic adjustment mode, set the target pressure reduction value at startup, the target pressure reduction value during normal operation, and the dead zone. When using manual start mode, set the opening degree at startup and the opening degree during normal operation. The circulating pump is set to one of the following: constant outlet pressure difference automatic adjustment, proportional automatic adjustment of outlet and inlet pressure difference, or manual frequency setting. When using constant outlet pressure difference automatic adjustment, set the target outlet pressure difference value at startup, the target outlet pressure difference value during normal operation, and the dead zone. When using proportional automatic adjustment of outlet and inlet pressure difference, set the target outlet pressure difference value at startup, the target outlet pressure difference value during normal operation, and the dead zone. When using manual frequency setting, set the frequency at startup and the frequency during normal operation. Step S4, Alarm Value Setting: Set the upper limit of outlet water supply pressure, the lower limit of outlet return water pressure, the upper limit of water supply temperature, power outage alarm, and abnormal pump stop alarm according to operational requirements; Step S5: After completing steps S1-S4, start the system according to the set parameters.

3. The working method of a direct-supply, temperature-difference-free pressure-reducing station intelligent system according to claim 2, characterized in that: The specific startup process for the manual startup mode in step S3 is as follows: Step a: After confirming that the instruments and valves are working properly, inject water into the primary water supply pipe to bring the system pressure to 0.25MPa. When injecting water, first manually open the electric butterfly valve VE1, then open the manual butterfly valves VM3, VM5, VM7, and VM8. Manually open the manual butterfly valve VM1 to about 5% of its opening, which needs to be adjusted in real time according to the rate of pressure change. Start injecting water into the system, closely monitor the system pressure, the water pump inlet pressure, pressure gauge PD8, and pressure sensor PT8. Ensure that the air vent valve is unobstructed during water injection. When the pressure reaches 0.25MPa, close the manual butterfly valve VM1. After closing the manual butterfly valve VM1, observe whether the system pressure drops. If it drops, vent and inject water again until the pressure stabilizes. Step b: After the pressure stabilizes, close the electric butterfly valve VE1, manual butterfly valves VM1, VM2, VM3, and VM5, while keeping manual butterfly valves VM7 and VM8 open. Start the water pump and slowly increase the speed. Simultaneously, open the electric pressure regulating valves VR1 and VR3. Reduce the pressure of electric pressure regulating valve VR1 to 0.5MPa and VR3 to 0.3MPa. Manually or automatically adjust the water pump frequency to reach the set parameters and run for at least 10 minutes. During this period, observe the water pump supply and return pressures and the pressure after the pressure regulating valves, and vent the air in time. If the water pump inlet pressure is too low, manually open the manual butterfly valve VM1, ensuring that the opening degree of manual butterfly valve VM1 is no more than 5%, to replenish water. Step c: After the operating parameters of electric pressure regulating valves VR1 and VR3 have reached a safe and reasonable state, open electric butterfly valves VE1 and VE2, and manually and slowly open manual butterfly valves VM1 and VM2. Observe the water pump supply and return pressures and the pressure after the electric pressure regulating valves. Manually or automatically adjust the water pump frequency to ensure a reasonable flow rate. After the water pump supply and return pressures and the electric pressure regulating valves have stabilized for 5 minutes, the program will automatically increase the pressure reduction value of electric pressure regulating valve VR1 to 0.65MPa and the pressure reduction value of electric pressure regulating valve VR3 to 0.45MPa. The water pump will be set to a reasonable value so that its flow rate reaches the required flow rate.

4. The working method of a direct-supply, temperature-difference-free pressure-reducing station intelligent system according to claim 2, characterized in that: The specific startup process for the automatic startup mode in step S3 is as follows: Step 1: Put manual butterfly valves VM1, VM2, VM7, and VM8 into the open state; and electric butterfly valves VE1, VE2, VM3, and VM5 into the closed state. Step II: After confirming that the instruments and valves are working properly, inject water into the primary water supply pipe to bring the system pressure to 0.25 MPa. If the system has already been injected with water and the pressure has reached 0.25 MPa, skip this step. When injecting water, first automatically open the electric butterfly valve VE1, with the opening of the electric butterfly valve VE1 being about 5%. Then open the electric pressure regulating valves VR1 and VR3. When the pressure sensor PT8 reaches 0.25 MPa, close the electric butterfly valve VE1. After closing the electric butterfly valve VE1, wait for 1 minute and observe whether the system pressure has decreased. If it has decreased, vent the air and inject water again until the pressure stabilizes. Step III: After the pressure stabilizes, close the electric butterfly valves VE1 and VE2, start the water pump, and slowly increase the speed. At the same time, open the electric pressure regulating valves VR1 and VR3. Reduce the pressure of electric pressure regulating valve VR1 to 0.5MPa and electric pressure regulating valve VR3 to 0.3MPa. Automatically adjust the water pump frequency to bring the water pump to the set parameters and run for at least 10 minutes. During this period, if the water pump inlet pressure is too low, automatically open the electric butterfly valve VE1 to replenish water until the pressure sensor PT8 reaches 0.25MPa. Step IV: After the operating parameters of the water pump, electric pressure regulating valve VR1, and electric pressure regulating valve VR3 have all reached a stable state, slowly open the electric butterfly valves VE1 and VE2. After the water pump supply and return pressures and the pressure regulating valves have stabilized for 5 minutes, slowly increase the pressure reduction value of electric pressure regulating valve VR1 to 0.65MPa and the pressure reduction value of electric pressure regulating valve VR3 to 0.45MPa. Also, set the water pump to a reasonable value so that the system flow rate reaches the required flow rate. Step V: Once the operating parameters are normal, it is considered to be in normal operating condition.

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